Cover plate



Nov. 28, 1944. H. w. BLAKEMAN 2,363,567

COVERPLATE Filed June l2, 1943 nventor BIJ *A l 5MM@ a coverplate that incorporates a l "wardly from the Patented Nov. 28, 1944 I UNITED STATES r1 tlr11e:N'1 oFFlcE N y .y M `2,363,557` K "l" roovlm PLATE f.Hem-yWQBlakeman,Rayville,La.4 t Application June 12, 1943, semaine. 490,693 i s olaims.- `Col. .ce2-6l My invention relates tocoverplates in general andmore especially toflocking type 'coverplates for submerged meteriboxesyvalve boxes,` manholes and the like. I

An object ofmy invention is to provide a coverplate` with a locking means that is operated by a key which serves also as a means for liftfV ing thecoverplate. l I

Another object of my invention is to provide Y `an auxiliary extension ring to adaptmy coverplate for useas a closing means for are wider` than my coverplate.

Another object of my inventionis to provide ocking means openings that so designed that the force of gravity assistslin the locking operation `and further Iassists l'in holding the locking means in locked position.

`Another object of my invention is'to provide a coverplate with a key type'locking means having its key contacting portions adapted `to be aligned `in position with the keyhole by means of thekey.

Other objects and advantages of my invention will appear from a reading of my detailed de` scription to follow of an embodiment of my invention illustratedby my drawing in which:

`Figure 1 is a broken planview of a coverplate `in closing position embodying -my invention, y

Figure 2 is-aoross sectional view of the coverplatetaken on line lul of Figure 1, andf Figure' `3 -is an enlarged fragxnentalView` of` a. portion ofthecovefplate `illustrated by Figures lande. t

The principal use that I now see for invention in a coverpl'ate 'isits use as a cover for a meter box in which 'the cover is designed to t a lan'ge on the top of the box which will correspond to the combination of the curb I and curb .extension ring '2 iillust'ratedin the drawing,` but for the purpose of illustrating the auxiliary ring extension' broadly mentionedas one of the obl :jects of my invention, I am showing my covery plate 5 as a manhole closingmeans.` j The curb I is permanently anchored into the manhole wall `M by means of the-hooksJ shown embedded in the manhole wall'M. The curb 2 is provided with two or more rS-in'g attaching lugs 3 through which extend threaded attaching bolts 4 of `lengths suncient to extend under the curb I to preventthe curb extensionring 2 from being lifted upwardly. The cov'erplate 5 rests v`on the curb extension :ri-ng 2 and is `lamented fromteingjuned upsame by means of the locking bars I0 forming a part of my locking means I `which'I shall now describe.`

I provide two or more wedge shaped centering t' lugs 6 onthe lowerfface o`f`my coverplate 5' in the curb extension ring`2. I provide also anaal-jA ditional pair of guide' lugs 1 which serve both as centering `means and guides for the locking i barsIIJ. The locking bars I0 extend also through ported solely bythe twoflockin'g bars IIJ. j I illustrate my `lockingrneans `in the locked position, that is Vwith the locking bars I0 shoved outwardly as "far as they `can go and 'resting on the bottom of the guide slots `9 Iii ' locking position with a' steep slanted slot being used, I do not depend upon `the source .of gravity alone to lock my cover.` I use a ,key K as 1a means :for closing and opening my locking mech-` anism and as a handle for `lifting the coverplate. I

extension ring depending curb `as shown by the solid lined positions of the loclting bars I0, as best seen in Figure 3. In the open position ofmy locking mechanism Vthe `locking bars I0 are drawrrinwardly` to the angular dotted lined positions, as best' seen in Figure Il, In Figure 3 the locking bar I0 is illustrated in its retracted position bythe dotted `circle as having been lifted to the top of the guide slot 9. It is easily seen `that by this arrangement the force of gravity pulling on fthe lockingbars IIl with the added weight of the throw cylinder I2 supported by them tends to pull the locking bars I0 down to the bottom ofthe slots to the locking position illustrated in the drawing.` vIt is also easy for the reader to appreciate that 'the force of gravity acting on the assembly of the two locking bars I0 andthe throw cylinder I2 1would `tend tokeep the locking bars Il) inthe outward. position or locking' position: aslsaid above. s l

While the assembly ofthe two locking bars* Ill and the throw cylinder I2 could be `made heavy enough to automatically throw themselves into When the locking barsyIIl are in the closed position, the vnared mouth keyslot I6, is in aligniment with the 4keyhole I5., 1n this aligned posi,-

ton the loeyK 1rru'tyloe :shoved through thetkey- 11016 15am! into the key slot I6 where it Vmay be of cast iron also.

preferably be made of steel. The manholewall:

` turned in the counter-clockwise direction, shown by the arrow in Figure 1, to withdraw the locking bars I as described above. The key K cannot be turned to the right at all in the closing position of the locking bars I0 because they are 5 down at the bottom of the guide slots 9. When the locking bars I0 are withdrawn, the blade K of the key K while still remaining in the key slot I6 is revolved around the underneath side of the coverplate tandv cannot be withdrawn.`

As a yconvenience in lifting vthe coverplate provide'my key K with a transverse extending lifting bar K at its top. These coverplates are generally made out of cast iron and are made very rugged and are therefore very heavy. i The; l5

curb I and extension ring 2 are generally made l The anchor bolts,` J would M illustrated as a masonary construction might l also be made out of `cast iron if desired.

Numeral I6 designates as stated above a flared mouth key slot which-isextended through the throw cylinder I2. Itis here pointed out that the slot does not necessarily have to extend entirely through the key slot I6 if the keyblade 5 K is made shorter. Under normal workingcondition's the key slot I6 is brought vinto neat alignu ment withithe keyhole I5 in the closed position of the lock in which case there would be no need But ldue toy inaccuracies in the Amanufacture of a cast device anddue to inaccuracies of align ment that Would'be broughtl about by the wearing of parts, I have provided the key slot I6 with a ared mouth so that should it at any time in 55 l the closed position of the lockingV meansbe brought into slight misalignment with the keyhole I5, it can be easily realignediby Amerely shoving the blade K of .the vkey K down into 4 the flared mouth of the keyvslot I6;

Having thus described my invention, I claimzm 1. A cover provided with alocking means at- Mtached` to its 'lower side, said locking means including a locking bar loosely reciprocally mounted in a guide depending -from the ,coverg4 said guide being provided with an upwardly slanting slot through which the locking bar extends, the` inner end of the locking bar being pivotably mounted `on a rotatable locking bar moving means, said locking bar moving means.;` being rotatably vmounted on the cover and being adapted to move the locking bar through the slanting slot while the locking bar moves across gof providing the key slot I6 with a flared mouthmgio the slanting slot whereby -the force of gravity acting onthe locking bar when'fthe` locking bar, is in an elevated position in the lslanting sloty assiststhe movement ofthe locking bar through the slanting slot. 'f

2. A cover provided with a locking means attached to its lower side, said locking means;vl including a locking bar loosely reciprocally mounted in a guide depending from the cover, said guide `being provided with an upwardly slanting slot through which the locking bar l extends, the locking bar beingpivotably mounted on a rotatable locking bar moving means, said locking bar moving means being loosely mounted on the cover and being supported by the said locking bar and being adapted to move the locking bar through the `upwardly slantingslot while i the locking bar moves across the slanting slot whereby 'the force of gravity acting on the locking bar and the locking bar moving means supported by it assists the movement of the locking bar through the slot when the locking bar is in an elevated position in the slot and a means for rotating the locking bar moving means.

3. A cover provided with a locking means attached to itsplower side, said locking means including a locking `bar loosely reciprocally mounted in a guide depending from the cover, said locking bar being extended also through a second guide provided with an upwardly slanting slot through whichgthe lockingl bar extends,

the inner end of the lockingbar beinglpivotably mounted on a rotatable locking bar moving means, said locking bar moving means being rotatably mounted on the cover and being .adapted to move the locking bar through the slanting slot while the locking bar moves across the slanting'slot whereby the force of gravity acting on the locking bar in an elevated position in the slanting slot assists the movement of the locking bar through the slanting slot.

4. `A cover provided with a l'locking means attached to its lower side, said locking means --including a lockingy bar loosely reciprocally mounted in a guide depending from the cover, said locking bar being extended through a second 'guide provided with an upwardly slanting slot through which the locking bar extends, the inner end of the locking bar beingpivotably mounted on a `rotatable locking bar moving means, said locking bar moving means beingl rotatably mounted on a boss depending from the cover adjacent to the second mentioned guide, said locking bar movingmeans being adapted to move the locking bar through the slanting slot while the locking bar moves across the slanting slot .whereby the force of gravity acting on the locking barfvin an elevated position inthe slanting 'slot assists the movement of the'I locking bar 0 through the slanting slot.

5. The device as claimed `-in claim 4 wherein the `locking bar moving means is loosely mounted on Athe boss and is supported by the locking bar Wherebythe force of gravity acting on the lock-- ing bar moving means assists the movement'of the locking bar throughtheslanting slot.

6. A cover provided with a locking means attached to its lower side, a cylindrical boss extending below the cover, a keyhole slot being extended through the cover and the depending boss, `a lockingbar reciprocally mounted in a guide depending from the underside of the cover,

the locking bar being pivotably mounted on a locking bar moving means, said locking `bar mov- Aing means being rotatably mounted on the 'boss and being `provided with a key slot positioned for alignment with the key slot extended through the cover and the-boss whereby a key extended through the cover and the boss may be placed in the slot in the lockingbar: moving means for turning the same.

7. The device as claimed in claim 6 wherein vthe key `slot inthe locking bar moving means is flared at its top opening to-assistthe alignment of the slot in the locking bar moving means with lthe slot in the depending boss.

8. A cover provided with a locking means attached to its lower side, said locking means including a plurality of locking bars reciprocally mounted in guides depending from the cover,

the inner ends of saidlocking bars being pivotably connected to a rotatable locking bar moving means provided with a `key slot, each of said `locking `bars being also extendedrthrough an additional guide provided with an upwardly slanting slot through which the locking bar extends whereby the force of gravity acting on the locking bars in elevated'positions in the slanting slots assists the movement of the looking bars through the slanting slots, the locking p bar moving means being rotatably mounted on a boss depending from the lower side of the cover, a. keyhole slot being extended through the cover `and the boss depending from the cover, the keyhole slot in the locking bar moving means being positioned for alignment with key slot extended through the cover and the boss whereby a, key

lextended through the cover and the boss may be placed into the keyhole slot in the locking bar `moving means to turn the same.

HENRY W. BLAKEMANv 

